There is established in the Department of Labor the office of Deputy Secretary of Labor, which shall be filled by appointment by the President, by and with the advice and consent of the Senate. The Deputy Secretary shall perform such duties as may be prescribed by the Secretary of Labor or required by law. The Deputy Secretary shall (1) in case of the death, resignation, or removal from office of the Secretary, perform the duties of the Secretary until a successor is appointed, and (2) in case of the absence or sickness of the Secretary, perform the duties of the Secretary until such absence or sickness shall terminate.